print report

Probably a stupid question from a newbie;
I have a form with several test results taken during a 24-hour priod.
Each test has a field with time format like this: yyyy-mm-dd hh:mm. (not primary key)
I want to print a report based on the data in to modes.
First one, specified by one particular time e.g. 2006-12-19 22:37.
That’s no problem. next one, I want to print out every report during one 24-hour period.
e.g. 2006-12-20 06:30
2006-12-20 15:32
2006-12-20 71:15

i.e. all report chosen by a specific date without any consideration to the time. I understand I have to format date somehow in VB but how? it will not work for me.